java - 无法从托管 bean 获取 session ID

Question

我有这个托管 bean:

package com.DX_57.SR_57;
/** include default packages for Beans */
import java.io.Serializable;
import javax.enterprise.context.SessionScoped;
   // or import javax.faces.bean.SessionScoped;
import javax.inject.Named;
/** include package for SHA-256 encryption */
import java.security.NoSuchAlgorithmException;
/** include SQL Packages */
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.sql.DataSource;
import javax.annotation.Resource;
import javax.faces.context.FacesContext;
import javax.inject.Inject;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
   // or import javax.faces.bean.ManagedBean;   
import org.DX_57.osgi.CL_27.api.CryptoSHA;
import org.glassfish.osgicdi.OSGiService;
import org.DX_57.osgi.SH_27.api.SessionHandle;


@Named("loginController")

@SessionScoped

public class userCheck implements Serializable {
    private String user = null;
    private String password = null;  
    private String error_Message = null;
    private String error_Database = null;

       public userCheck(){
       }

       /** Call the Oracle JDBC Connection driver */
       @Resource(name="jdbc/Oracle")
       private DataSource ds;

       /** Call OSGI Bundle SH_27 SessionHandle Library */
       /** Use transient in order to disable serialization when calling OSGI Bundle */
       @Inject @OSGiService(dynamic=true) transient SessionHandle SH;

       public String OSGISHCheckUserDB(String CheckUser) throws SQLException{        
            return SH.CheckUserDB(CheckUser);
       }

       public String OSGISHSessionRegister(String User) throws SQLException{        
            return SH.SessionRegister(User);
       }

       /** Call OSGI Bundle CL_27 Crypto Library */
       /** Use transient in order to disable serialization when calling OSGI Bundle */
       @Inject @OSGiService(dynamic=true) transient CryptoSHA CL;

       public String OSGICLShaEncryptHash(String CString) throws NoSuchAlgorithmException{        
            return CL.ShaEncryptHash(CString);
       }      

       /** get the content of the variables from the JSF Login page */
       public void setUser(String newValue) { 
           user = newValue; 
       }

       public String getUser(){
           return user;       
       }

       public void setPassword(String newValue) { 
           password = newValue; 
       } 

       public String getPassword(){
           return password;
       }

       public String geterror_Database(){
           return error_Database;
       }

       public String geterror_Message(){
           return error_Message;
       }


       /** get user session id */
       FacesContext fCtx = FacesContext.getCurrentInstance();
       HttpSession session = (HttpSession) fCtx.getExternalContext().getSession(false);
       String sessionId = session.getId();             

       /** get user IP address */           
       FacesContext context = FacesContext.getCurrentInstance();
       HttpServletRequest request = (HttpServletRequest)context.getExternalContext().getRequest();
       String remoteHost = request.getRemoteAddr();



       /** compare the user and the password */
       public String userCompare() throws NoSuchAlgorithmException, SQLException { 
            String hash_passwd = null;           
            String passwdQuery = null;

            /** check the password into Oracle using the username */
            passwdQuery = OSGISHCheckUserDB(user);

            /** convert the plain password in SHA-256 hash */
//          hash_passwd = string_hash(password); 

            /** compare the encrypted passwords */
            if (password.equals(passwdQuery)){     
                /** insert into users session table the time when the user login */
//                SessionRegister(user);
                /* success */                                 
                return "0";       
            } else {  
                /* failer */ 
                return "1";              
            }            
       }   

}

我可以使用 Netbeans 成功编译它。当我将其部署在 Glassfish 上并打开它时，我收到以下错误堆栈:

[#|2012-02-04T18:29:36.554+0200|INFO|glassfish3.1.1|org.glassfish.osgijavaeebase|_ThreadID=64;_ThreadName=Thread-2;|deployed bundle com.DX_57.SR_57 [296] at file:/tmp/osgiapp4499752333201324876/|#]

[#|2012-02-04T18:29:48.047+0200|SEVERE|glassfish3.1.1|javax.enterprise.resource.webcontainer.jsf.application|_ThreadID=143;_ThreadName=Thread-2;|Error Rendering View[/home.xhtml]
com.sun.faces.mgbean.ManagedBeanCreationException: Cant instantiate class: com.DX_57.SR_57.userCheck.
    at com.sun.faces.mgbean.BeanBuilder.newBeanInstance(BeanBuilder.java:193)
    at com.sun.faces.mgbean.BeanBuilder.build(BeanBuilder.java:102)
    at com.sun.faces.mgbean.BeanManager.createAndPush(BeanManager.java:409)
    at com.sun.faces.mgbean.BeanManager.create(BeanManager.java:269)
    at com.sun.faces.el.ManagedBeanELResolver.resolveBean(ManagedBeanELResolver.java:244)
    at com.sun.faces.el.ManagedBeanELResolver.getValue(ManagedBeanELResolver.java:116)
    at com.sun.faces.el.DemuxCompositeELResolver._getValue(DemuxCompositeELResolver.java:176)
    at com.sun.faces.el.DemuxCompositeELResolver.getValue(DemuxCompositeELResolver.java:203)
    at com.sun.el.parser.AstIdentifier.getValue(AstIdentifier.java:99)
    at com.sun.el.parser.AstValue.getValue(AstValue.java:158)
    at com.sun.el.ValueExpressionImpl.getValue(ValueExpressionImpl.java:219)
    at com.sun.faces.facelets.el.TagValueExpression.getValue(TagValueExpression.java:109)
    at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:194)
    at javax.faces.component.ComponentStateHelper.eval(ComponentStateHelper.java:182)
    at javax.faces.component.UIOutput.getValue(UIOutput.java:169)
    at com.sun.faces.renderkit.html_basic.HtmlBasicInputRenderer.getValue(HtmlBasicInputRenderer.java:205)
    at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.getCurrentValue(HtmlBasicRenderer.java:355)
    at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.encodeEnd(HtmlBasicRenderer.java:164)
    at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:875)
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1763)
    at javax.faces.render.Renderer.encodeChildren(Renderer.java:168)
    at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:845)
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1756)
    at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1759)
    at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:401)
    at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:131)
    at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:121)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
    at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:139)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:594)
    at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1539)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
    at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:98)
    at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:91)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:162)
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:330)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:174)
    at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:828)
    at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:725)
    at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1019)
    at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:225)
    at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
    at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
    at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
    at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
    at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
    at java.lang.Thread.run(Thread.java:722)
Caused by: java.lang.NullPointerException
    at com.DX_57.SR_57.userCheck.<init>(userCheck.java:103)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:525)
    at java.lang.Class.newInstance0(Class.java:372)
    at java.lang.Class.newInstance(Class.java:325)
    at com.sun.faces.mgbean.BeanBuilder.newBeanInstance(BeanBuilder.java:188)
    ... 54 more
|#]

问题出在以下几行:

 /** get user session id */
       FacesContext fCtx = FacesContext.getCurrentInstance();
       HttpSession session = (HttpSession) fCtx.getExternalContext().getSession(false);
       String sessionId = session.getId();

您能给我一些如何解决这些问题的建议吗？

Answer 1

罪魁祸首在这里:

...getExternalContext().getSession(false);

阅读javadoc boolean 参数的作用是什么。

If the create parameter is true, create (if necessary) and return a session instance associated with the current request. If the create parameter is false return any existing session instance associated with the current request, or return null if there is no such session.